Super Best Audio Friends

To be absolutely clear, both THD and THD+N are not completely useless measurements. However, when interpreting these numbers, it is of vital importance to keep in mind what they represent. THD is essentially a summation of all of the harmonics, i.e. 2nd harmonics, 3rd, 4th, etc, and outputted as a single number. The “+N” part, the noise, refers to things like mains noise. This measurement is most useful just as a quick and dirty way to see the harmonic distortion present within a system; however, there are several problems with this singular number approach, some of which I will attempt to identify and explain here. The goal is to be able to explain the dated nature of THD using the examples of some amplifiers, explain how to use the individual harmonic measurements to help extrapolate sonic characteristics from looking at measurements, and introduce @atomicbob’s “crap factor,” which @atomicbob believes to be a much more useful measurement when talking about the bad stuff we don’t like listening to. Keep in mind that I am not downplaying the importance of subjective impressions (after all, we listen to music and not sit there and listen to 1kHz sinusoids), but rather is an attempt to help this community understand the thoroughly detailed measurements that @atomicbob, @purr1n, and others post, how they might correlate to things that you hear, and how to use them to help match the measurements with your personal preferences. After all, Changstar was founded upon the idea of measurements, and measurements should serve as a basis to at least keep us honest.

With packages being delivered tonight, it is time to put on our asbestos gear and get ready for the flame wars.

I propose a round of out-of-the-box hot takes before we get all clinical. Who’s got ‘em already?

Impressions and/or measurements:

• https://www.superbestaudiofriends.o...troversial-hd-660s2-thread.13205/#post-403475
• https://www.superbestaudiofriends.o...troversial-hd-660s2-thread.13205/#post-403687
• https://www.superbestaudiofriends.o...sial-hd-660s2-thread.13205/page-2#post-403745
  
• https://www.superbestaudiofriends.o...sial-hd-660s2-thread.13205/page-2#post-403781
• https://www.superbestaudiofriends.o...sial-hd-660s2-thread.13205/page-2#post-403843

I think Amir brings up a good point, from a scientific point of view, that we need statistical analysis.


So here we go. Similar methodology as last time:

1. 1kHz test tone, measured via DMM, to match levels within 1/100 Vrms
2. All units left on for at least one hour.
3. Double blind test: I got my kids to change up the wires into the amps headphone output randomly while I wasn't in the room and then I asked them to leave the room in another direction of which I entered the room.
4. Wires occluded so I could not see them during the ABX test.

• I had been doing home audition of Orchard Starkrimson amp since last Thursday.
• It sounds very transparent with lot of detials.
• I also have Schitt Aegir which I had enjoyed for last two months for warm and full bodied sound.
• But Aegir sounds opaque compared with Starkrimson.
• This moring I had compared with my friend's Dartzeel 108, Starkrimson and my Line Magnetic 508 fitted with vintage tubes.
• He really like my Line Magnetic 508.
• Dartzeel 108 falls short of my tube amp in overall musicality.
• He is also of opinion that as good as Starkrimson is, it sounds somewhat thin compared with Dartzeel 108.
• He had auditioned Atmashphere D class amp for 10 days at his home.
• He is of the opinion that Atma sounds fuller than Starkrimson.
• Thus despite the higher price, He prefer Atma to Starkrimson.
• But I am of the opinion that Starkrimson is a good value and tunable with tube pre amp.

This is the JAR6XX. Read all about this headphone at the Jupiter Audio Research website. The idea behind the JAR6XX is similar to that of the various mass loading and filter adjustment modifications to the HD6XX/650 discussed here. Except JAR takes it to the next level. @CEE TEE sent these over to me to compare to the JAR600, which I happen to use as my daily driver (on most days where I want something neutral sounding).



JAR6XX
Frequency Response
CYAN = left, RED = right

This time around, I felt differently, much differently. This one most certainly deserves it's own thread. And oh, by the way, the "Audeze x Rhythmdevils" and "Definitive Edition" was my touch 100%. No one put me up to it. This is how much I'm impressed with it. Or maybe it's those shiny new Western Electric 300B tubes affecting my mind. Whitney has been sending me a bunch of modded headphones for the past year. Most of them are good. Some of them are very good. He solicits input and I tell him how it is without bullshiting or fluffing him up. This is why he sends stuff to me, being ever super duper patient until I get to them. Then going back to his lab, tweaking stuff iteratively, until something really specially happens. Wanna know a secret about good audio gear? It's that last 5% of performance that makes something click. And that last 5% takes 95% of the effort.



The Audeze x RhythmDevils LCD-X Definitive Edition is f'ing good. These are overall the best Audeze headphones I have ever heard. It's not even close. Tonally it's the best. Technical performance, maybe the LCD-4 just pips it a bit (and this was a handpicked LCD-4 from a dozen). Note that I have not heard Audeze's latest and greatest. If I had to use a Japanese RPG character tiering system, I'd give the tonal signature an S- and technical performance A+.

External Switch Mode Power Supplies are included with many headphone amps as a way to keep cost and shipping weight down, except Schiit which use external transformers with true Linear Power Supplies internal to the chassis in their lower cost products. SMPS offer higher efficiency, less heat, smaller size and weight. Unfortunately they often have higher residual noise which does affect amplifier performance. SMPS vs. LPS effect on an example headphone amplifier may be found here:
SMPS vs LPS effect on Garage1217 Project Sunrise III

The following single massive stage LC filter will reduce SMPS residual ripple and noise. Parts cost was approximately $42 US in component single unit quantities, and about 2 hours of construction time. It will work with any external SMPS or LPS between 1 and 48 VDC with current less than 2A. Examples include Garage1217 and the Massdrop Cavalli Tube Hybrid (MCTH) headphone amps.

Hi everybody! As some of you may know, we started up a local discord community centered around rebuilding the bustling Bay Area community that was before the pandemic. We have been having monthly mini meets and it's time we leveled up. We are announcing our first big meet. This will be open to everyone but it will be capacity limited to 100 200 attendees. As such, we have created an eventbrite to keep that limitation in mind (but it is entirely free). Also, we want to make sure this event is community driven. We want our community to be able to come out and share their gear and be able to try other gear on their setups. Because of limited table space, we will be taking interested parties' details and then selecting who will be able to bring in their setups. This will be handled by DM'ing Nick or Vince in the discord channel (link below). That being said, if you have headphones or IEMs (or even DAPs) that are portable, feel free to bring those with you and carry those around to test out all the cool stuff that will be there. So here are the details:

Important notes:

1. You will need to present your ticket at the table and receive a name tag. This ensures that we are keeping within the capacity limitations of the venue.
2. If you are selected to bring your own setup, please arrive 2 hours before the event to set up. There will also be 2 hours after the event is over to break down and pack up.
3. There might be food but this is still being worked out.
4. Gear list to come.

We are sponsored by Schiit Audio!!! Please thank them for helping us put together this meet and be able to enjoy this bigger venue and the space needed to bring more of us together! Also for sending us gear to try out! With all the new stuff they just announced, man this is going to be a good one!

Listening evaluation picture:

Zen Taboo mk4 inputs switched between Holo Spring 2 KTE Bal & SE outputs. Most listening evaluation with gain set to High, crossfeed bypassed, amp volume set for 0 dB gain with Goldpoint SA2X and SA2 external stepped attenuators employed to set level. There are plenty of impressions threads on the forum where more detailed and nuanced thoughts about the various components are discussed. For my preferences, either I like how a system renders music or I don’t.

Notable highlights:
Due to some interesting attributes of this amp I will provide additional commentary and interpretation from which I would normally refrain.

Decware Zen Taboo tonality has always impressed me during listening sessions at various meets. Typically with HD800 headphones and yggdrasil DAC. Meet conditions are often burdened with higher ambient room noise than my dedicated lab listening environment. With the opportunity to hear this wonderful amp in my own setting, the tonality continued to impress.

Let's start with measurements first. BTW, I really love the timbre** of the Supermoon. More later...

They're basically a kit with MKII headband, MKIII drivers, various dampening materials, two sets of ear pads, and two cables. One of the fellas here posted an ebay link of these open box kits from the UK ,and they accepted my offer of $100 shipped. Everything in the pic below was included, the sticker packs as well, and they appeared to be brand new. The instructions have an English expanation of the various dampeners and mods. Since these are the MKIII drivers with the little window on the back side dampening material, I was surprised to see a tiny piece of foam that can be plugged into that spot that "dampens lower frequency". I haven't tried that option yet though.



All in all a fun mini project for dirt cheap that took me back to the roots of my addiction to this hobby. Here are a few quick raw measurements I took. The drivers are matched quite well, with a slight leak probably being the culprit of the different low end between channels. Also during a frequency sweep I could hear the Right driver slightly flutter down low and it shows up in the distortion plot as significantly higher down there than the Left.

Been keeping my thoughts to myself. I've had a few PMs. Let's discuss with those who got them.




P.S. Or just ask me questions. (I've already traded notes with other members).